In a frying pan or a wok, heat oil, then sauté lemongrass and garlic until aromatic.
Add in the harder pieces of asparagus first (the lower parts of the stalk), and stir-fry for about one minute.
Then add in the rest of the asparagus, and the coconut milk, water, bell pepper, fish sauce, and Thai bird’s eye chili (if using). Stir and toss to make sure the asparagus cooks evenly. Bring it to a boil, then lower the heat.
Season with salt and galangal powder. Stir and let simmer for two minutes or until asparagus spears are tender (test
by cutting through one – it should be easy to cut, but still crunchy).
Add in a bit more water/coconut milk if you like it to be more saucy. Taste and adjust any seasonings.
Dish out, sprinkle with some ground white pepper, squeeze in lime juice, and garnish with slices of red serrano chili. Serve hot with steamed rice.